A conventional embroidery sewing machine includes a sewing machine body; a cloth holding frame that holds a workpiece cloth in a stretched manner; a frame drive unit that drives the cloth holding frame independently in two mutually perpendicular directions in a horizontal plane. Provided in an arm of the sewing machine body is a needle bar vertically moving mechanism that vertically moves the needle bar. Also, various types of loop takers are provided in a bed of the sewing machine body. Household embroidery sewing machines having the frame drive unit installed in the bed of the sewing machine body have been reduced to practice in the household sewing machine field also.
In recent years, embroidery sewing machines have been suggested that allow both embroidery and print images to be formed on the workpiece cloth. In such embroidery sewing machines, an ink-jet print head is disposed in the proximity of the upper surface of the workpiece cloth which is held by the cloth holding frame linked to the frame drive unit; and the print head prints various patterns and graphics directly on the workpiece cloth by moving the cloth holding frame in the horizontal direction by the frame drive unit.
For example, JP-A-H09-256260 discloses an embroidery sewing machine as described as follows (refer to pages 3 to 4, and FIGS. 2 and 3 in particular). The disclosed embroidery sewing machine is a multi-headed sewing machine incorporating two embroidery sewing machines. A plurality of needle bars and one print head are provided in a color changing mechanism of each embroidery sowing machine. In response to an input of embroidery data upon needle bar selection, the sewing needle is driven and a rectangular embroidery frame is further moved in X-Y direction. Thus, the intended embroidery pattern can be sewn. By selecting a print head, the embroidery frame is moved in X-Y direction based on the inputted print data, thereby allowing the execution of a color printing operation with colors such as cyan, magenta and yellow. More specifically, when executing a printing operation, ink is ejected from the print head in synchronism with the reciprocating movement of the embroidery frame (workpiece cloth) moving in one way at a time in the X-direction; whereupon completion of printing one print line (one way), the embroidery frame is fed by one print line in the Y-direction and the process repeats itself thereafter.
Patent document 1: JP-A-H09-256260